Tire building apparatus

Abstract

A tire building apparatus includes a former made of a plurality of segment units arranged in a circumference, an inner shaft extending through the former, an outer shaft and a sleeve mounted on the inner shaft, the outer shaft and the sleeve carrying a right guide mechanism, a left guide mechanism, a right slider, and a left slider respectively, a right link mechanism, and left link mechanism provided between the right slider and the right guide mechanism, a left link mechanism provided between the left slider and the left guide mechanism. Another tire building apparatus includes a former made of a plurality of segment units arranged having a center segment, a right side segment, and a left side segment, and a right moving device for moving the right side segment in axial and radial directions, a left moving device for moving the left side segment in axial and radial directions, and a center segment support device for supporting the center segment with radially inward biasing. The former can be set into an axially expanded state, an axially contracted state, a radially expanded state, and a radially contracted state.

What is claimed is: 
     
       1. A tire building apparatus comprising: former means including a plurality of segment units arranged in a circumference, each of said segment units having at least a right side segment, a left side segment, a center segment, and center segment support means for supporting said center segment in a central portion of said former means;   an inner shaft extending through said former means;   an outer hollow shaft mounted on said inner shaft;   a sleeve mounted on said inner shaft;   right guide means provided between said right side segment and said outer hollow shaft for guiding movement of said right side segment in a radial direction and an axial direction;   left guide means provided between said left side segment and said sleeve for guiding movement of said left side segment in a radial direction and in an axial direction;   right slider means axially slidably mounted on said outer hollow shaft;   left slider means axially slidably mounted on said sleeve;   a right link mechanism provided between said right guide means and said right slider means for moving said right side segment in a radial direction in accordance with an axial movement of said right slider means; and   a left link mechanism provided between said left guide means and said left slider means for moving said left side segment in a radial direction in accordance with an axial movement on said left slider means;   whereby said outer hollow shaft and said sleeve are moved farther away from each other so as to set said former means into an axially expanded state, said right slider means and said left slider means are moved closer to each other so as to set said former means into a radially expanded state, said outer hollow shaft and said sleeve are moved closer to each other so as to set said former means into an axially contracted state, and said right slider means and said left slider means are moved further away from each other so as to set said former means into a radially contracted state, and whereby said center segment support means causes said right and left side segments to slide underneath said center segment when said former means is in said axially contracted state.   
     
     
       2. A tire building apparatus according to claim 1 wherein said slider means includes an expandable bladder for turning up a side end portion of a carcass around a bead ring. 
     
     
       3. A tire building apparatus according to claim 2 wherein said slider means further includes pressing means for pressing said bladder to said bead ring around which said side end portion of said carcass has been turned up. 
     
     
       4. A tire building apparatus according to claim 1 wherein: said right side segment includes a right end having a face perpendicular to an axis of said inner shaft; and   said left segment includes a left end having a face perpendicular to said axis of said inner shaft.   
     
     
       5. A tire building apparatus according to claim 1 wherein said center segment support means includes: right moving means for moving said right side segment in at least an axial direction;   left moving means for moving said left side segment in at least an axial direction;   an axially extended rod attached to one of said right or left moving means;   an element radially movably attached to said center segment and slidably supported by said axially extended rod;   a first biasing member provided on said element for biasing said center segment in an inner radial direction so as to bring said center segment into contact with said right side segment and said left side segment; and   a second biasing member provided between one of said right or left moving means and said element for biasing said element toward the other side segment when both of the side segments are moved closer to each other.   
     
     
       6. A tire building apparatus comprising: former means including a plurality of segment units arranged in a circumference, each of aid segment units having; a center segment, a right side segment, and a left side segment,   right moving means for moving said right side segment in at least an axial direction;   left moving means for moving said left side segment in at least an axial direction; and   center segment support means for supporting said center segment in a central position of said former means, said center segment support means including:   an axially extending rod attached to one of said left or right moving means;   an element radially movably attached to said center segment and slidably supported by said axially extended rod;   a first biasing member provided on said element for biasing said center segment in an inner radial direction so as to bring said center segment into contact with said right side segment and said left side segment; and   a second biasing member provided between one of said right or left moving means and said element for biasing said element toward the other side segment when both of the side segments are moved closer to each other.